Synthetic vision systems display the location of a destination airfield through the device of a dome centered on the airfield, as well as range to the airfield thru the device of a synthetic extended centerline for the selected runway (runway extended centerline), graduated with crossbars at 10, 5, and 3 miles from the runway threshold labeled with appropriate distance-remaining billboard markers, which fade based on proximity, as well as 2 and 1 mile crossbars without distance billboards. An equivalent presentation is displayed on a head-up display (HUD) with some HUD-specific features, and can be extended to head-worn display (HWD) systems.
When the airfield is nearby but outside the field of view of the display presentation, the crew no longer has situational awareness of airfield proximity, which is problematic especially on a short final leg. Consequently, it would be advantageous if an apparatus existed that is suitable for displaying distance markers to an airfield even when the airfield is not presented on a display.